National Collection of Amphibians and Reptiles - With over 500,000 specimens from round the world, this collection is located in Washington, DC, USA. Living Amphibians - Introduction to the taxonomy of Amphibia, including Salientia (frogs and toads), Caudata (salamanders and newts), and gymnophiona (caecilians). AmphibiaWeb - Source for amphibian data and conservation resources. Amphibian Species of the World - A searchable catalog of the recognized amphibian species of the world with synonymies and references to the taxonomic literature. Canada's AquaticEnvironment: Amphibians - Explores morphology, ecology and evolution. USGS: Patuxent Wildlife Research Center - National Amphibian Atlas - A compilation of current and historic records of amphibian occurrences in the United States, with range maps for each species to the county level.